/*
 * SonarQube
 * Copyright (C) 2009-2017 SonarSource SA
 * mailto:info AT sonarsource DOT com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.sonar.scanner.scan;

import java.util.HashMap;
import java.util.Map;

import org.picocontainer.injectors.ProviderAdapter;
import org.sonar.api.batch.bootstrap.ProjectDefinition;
import org.sonar.api.batch.bootstrap.ProjectReactor;
import org.sonar.api.batch.fs.internal.DefaultInputModule;
import org.sonar.scanner.scan.filesystem.BatchIdGenerator;

public class InputModuleHierarchyProvider extends ProviderAdapter {

  private DefaultInputModuleHierarchy hierarchy = null;

  public DefaultInputModuleHierarchy provide(ProjectBuildersExecutor projectBuildersExecutor, ProjectReactorValidator validator,
    ProjectReactor projectReactor, BatchIdGenerator batchIdGenerator) {
    if (hierarchy == null) {
      // 1 Apply project builders
      projectBuildersExecutor.execute(projectReactor);

      // 2 Validate final reactor
      validator.validate(projectReactor);

      // 3 Create modules and the hierarchy
      DefaultInputModule root = new DefaultInputModule(projectReactor.getRoot(), batchIdGenerator.get());
      Map<DefaultInputModule, DefaultInputModule> parents = createChildren(root, batchIdGenerator, new HashMap<>());
      if (parents.isEmpty()) {
        hierarchy = new DefaultInputModuleHierarchy(root);
      } else {
        hierarchy = new DefaultInputModuleHierarchy(parents);
      }
    }
    return hierarchy;
  }

  private static Map<DefaultInputModule, DefaultInputModule> createChildren(DefaultInputModule parent, BatchIdGenerator batchIdGenerator,
    Map<DefaultInputModule, DefaultInputModule> parents) {
    for (ProjectDefinition def : parent.definition().getSubProjects()) {
      DefaultInputModule child = new DefaultInputModule(def, batchIdGenerator.get());
      parents.put(child, parent);
      createChildren(child, batchIdGenerator, parents);
    }
    return parents;
  }
}
